In conventional skin diagnosis, a professional skin analysis apparatus is often involved to obtain information of skin conditions. To provide a final diagnosis, however, not only does it require a highly-trained professional (typically a dermatologist) to operate the apparatus, but it also entails his or her professional judgment on the skin analysis results rendered by the apparatus. Then, according to the diagnosis, the professional can recommend skin care products or treatments to the patients. To the general public, the conventional skin analysis apparatus is not readily accessible to install or operate.